1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AMD Secure Encrypted Virtualization (SEV) interface 4 * 5 * Copyright (C) 2016,2019 Advanced Micro Devices, Inc. 6 * 7 * Author: Brijesh Singh <brijesh.singh@amd.com> 8 */ 9 10 #include <linux/bitfield.h> 11 #include <linux/module.h> 12 #include <linux/kernel.h> 13 #include <linux/kthread.h> 14 #include <linux/sched.h> 15 #include <linux/interrupt.h> 16 #include <linux/spinlock.h> 17 #include <linux/spinlock_types.h> 18 #include <linux/types.h> 19 #include <linux/mutex.h> 20 #include <linux/delay.h> 21 #include <linux/hw_random.h> 22 #include <linux/ccp.h> 23 #include <linux/firmware.h> 24 #include <linux/panic_notifier.h> 25 #include <linux/gfp.h> 26 #include <linux/cpufeature.h> 27 #include <linux/fs.h> 28 #include <linux/fs_struct.h> 29 #include <linux/psp.h> 30 #include <linux/amd-iommu.h> 31 #include <linux/crash_dump.h> 32 33 #include <asm/smp.h> 34 #include <asm/cacheflush.h> 35 #include <asm/e820/types.h> 36 #include <asm/sev.h> 37 #include <asm/msr.h> 38 39 #include "psp-dev.h" 40 #include "sev-dev.h" 41 42 #define DEVICE_NAME "sev" 43 #define SEV_FW_FILE "amd/sev.fw" 44 #define SEV_FW_NAME_SIZE 64 45 46 /* Minimum firmware version required for the SEV-SNP support */ 47 #define SNP_MIN_API_MAJOR 1 48 #define SNP_MIN_API_MINOR 51 49 50 /* 51 * Maximum number of firmware-writable buffers that might be specified 52 * in the parameters of a legacy SEV command buffer. 53 */ 54 #define CMD_BUF_FW_WRITABLE_MAX 2 55 56 /* Leave room in the descriptor array for an end-of-list indicator. */ 57 #define CMD_BUF_DESC_MAX (CMD_BUF_FW_WRITABLE_MAX + 1) 58 59 static DEFINE_MUTEX(sev_cmd_mutex); 60 static struct sev_misc_dev *misc_dev; 61 62 static int psp_cmd_timeout = 100; 63 module_param(psp_cmd_timeout, int, 0644); 64 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands"); 65 66 static int psp_probe_timeout = 5; 67 module_param(psp_probe_timeout, int, 0644); 68 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe"); 69 70 static char *init_ex_path; 71 module_param(init_ex_path, charp, 0444); 72 MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); 73 74 static bool psp_init_on_probe = true; 75 module_param(psp_init_on_probe, bool, 0444); 76 MODULE_PARM_DESC(psp_init_on_probe, " if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it"); 77 78 #if IS_ENABLED(CONFIG_PCI_TSM) 79 static bool sev_tio_enabled = true; 80 module_param_named(tio, sev_tio_enabled, bool, 0444); 81 MODULE_PARM_DESC(tio, "Enables TIO in SNP_INIT_EX"); 82 #else 83 static const bool sev_tio_enabled = false; 84 #endif 85 86 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */ 87 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */ 88 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */ 89 MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */ 90 91 static bool psp_dead; 92 static int psp_timeout; 93 94 enum snp_hv_fixed_pages_state { 95 ALLOCATED, 96 HV_FIXED, 97 }; 98 99 struct snp_hv_fixed_pages_entry { 100 struct list_head list; 101 struct page *page; 102 unsigned int order; 103 bool free; 104 enum snp_hv_fixed_pages_state page_state; 105 }; 106 107 static LIST_HEAD(snp_hv_fixed_pages); 108 109 /* Trusted Memory Region (TMR): 110 * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator 111 * to allocate the memory, which will return aligned memory for the specified 112 * allocation order. 113 * 114 * When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB sized. 115 */ 116 #define SEV_TMR_SIZE (1024 * 1024) 117 #define SNP_TMR_SIZE (2 * 1024 * 1024) 118 119 static void *sev_es_tmr; 120 static size_t sev_es_tmr_size = SEV_TMR_SIZE; 121 122 /* INIT_EX NV Storage: 123 * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page 124 * allocator to allocate the memory, which will return aligned memory for the 125 * specified allocation order. 126 */ 127 #define NV_LENGTH (32 * 1024) 128 static void *sev_init_ex_buffer; 129 130 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic); 131 132 static int snp_shutdown_on_panic(struct notifier_block *nb, 133 unsigned long reason, void *arg); 134 135 static struct notifier_block snp_panic_notifier = { 136 .notifier_call = snp_shutdown_on_panic, 137 }; 138 139 static inline bool sev_version_greater_or_equal(u8 maj, u8 min) 140 { 141 struct sev_device *sev = psp_master->sev_data; 142 143 if (sev->api_major > maj) 144 return true; 145 146 if (sev->api_major == maj && sev->api_minor >= min) 147 return true; 148 149 return false; 150 } 151 152 static void sev_irq_handler(int irq, void *data, unsigned int status) 153 { 154 struct sev_device *sev = data; 155 int reg; 156 157 /* Check if it is command completion: */ 158 if (!(status & SEV_CMD_COMPLETE)) 159 return; 160 161 /* Check if it is SEV command completion: */ 162 reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 163 if (FIELD_GET(PSP_CMDRESP_RESP, reg)) { 164 sev->int_rcvd = 1; 165 wake_up(&sev->int_queue); 166 } 167 } 168 169 static int sev_wait_cmd_ioc(struct sev_device *sev, 170 unsigned int *reg, unsigned int timeout) 171 { 172 int ret; 173 174 /* 175 * If invoked during panic handling, local interrupts are disabled, 176 * so the PSP command completion interrupt can't be used. Poll for 177 * PSP command completion instead. 178 */ 179 if (irqs_disabled()) { 180 unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10; 181 182 /* Poll for SEV command completion: */ 183 while (timeout_usecs--) { 184 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 185 if (*reg & PSP_CMDRESP_RESP) 186 return 0; 187 188 udelay(10); 189 } 190 return -ETIMEDOUT; 191 } 192 193 ret = wait_event_timeout(sev->int_queue, 194 sev->int_rcvd, timeout * HZ); 195 if (!ret) 196 return -ETIMEDOUT; 197 198 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 199 200 return 0; 201 } 202 203 static int sev_cmd_buffer_len(int cmd) 204 { 205 switch (cmd) { 206 case SEV_CMD_INIT: return sizeof(struct sev_data_init); 207 case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex); 208 case SEV_CMD_SNP_SHUTDOWN_EX: return sizeof(struct sev_data_snp_shutdown_ex); 209 case SEV_CMD_SNP_INIT_EX: return sizeof(struct sev_data_snp_init_ex); 210 case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status); 211 case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr); 212 case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import); 213 case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export); 214 case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start); 215 case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data); 216 case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa); 217 case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish); 218 case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure); 219 case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate); 220 case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate); 221 case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission); 222 case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status); 223 case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg); 224 case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg); 225 case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start); 226 case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data); 227 case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa); 228 case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish); 229 case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start); 230 case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish); 231 case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data); 232 case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa); 233 case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret); 234 case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware); 235 case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id); 236 case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report); 237 case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel); 238 case SEV_CMD_SNP_GCTX_CREATE: return sizeof(struct sev_data_snp_addr); 239 case SEV_CMD_SNP_LAUNCH_START: return sizeof(struct sev_data_snp_launch_start); 240 case SEV_CMD_SNP_LAUNCH_UPDATE: return sizeof(struct sev_data_snp_launch_update); 241 case SEV_CMD_SNP_ACTIVATE: return sizeof(struct sev_data_snp_activate); 242 case SEV_CMD_SNP_DECOMMISSION: return sizeof(struct sev_data_snp_addr); 243 case SEV_CMD_SNP_PAGE_RECLAIM: return sizeof(struct sev_data_snp_page_reclaim); 244 case SEV_CMD_SNP_GUEST_STATUS: return sizeof(struct sev_data_snp_guest_status); 245 case SEV_CMD_SNP_LAUNCH_FINISH: return sizeof(struct sev_data_snp_launch_finish); 246 case SEV_CMD_SNP_DBG_DECRYPT: return sizeof(struct sev_data_snp_dbg); 247 case SEV_CMD_SNP_DBG_ENCRYPT: return sizeof(struct sev_data_snp_dbg); 248 case SEV_CMD_SNP_PAGE_UNSMASH: return sizeof(struct sev_data_snp_page_unsmash); 249 case SEV_CMD_SNP_PLATFORM_STATUS: return sizeof(struct sev_data_snp_addr); 250 case SEV_CMD_SNP_GUEST_REQUEST: return sizeof(struct sev_data_snp_guest_request); 251 case SEV_CMD_SNP_CONFIG: return sizeof(struct sev_user_data_snp_config); 252 case SEV_CMD_SNP_COMMIT: return sizeof(struct sev_data_snp_commit); 253 case SEV_CMD_SNP_FEATURE_INFO: return sizeof(struct sev_data_snp_feature_info); 254 case SEV_CMD_SNP_VLEK_LOAD: return sizeof(struct sev_user_data_snp_vlek_load); 255 default: return sev_tio_cmd_buffer_len(cmd); 256 } 257 258 return 0; 259 } 260 261 static struct file *open_file_as_root(const char *filename, int flags, umode_t mode) 262 { 263 struct path root __free(path_put) = {}; 264 265 task_lock(&init_task); 266 get_fs_root(init_task.fs, &root); 267 task_unlock(&init_task); 268 269 CLASS(prepare_creds, cred)(); 270 if (!cred) 271 return ERR_PTR(-ENOMEM); 272 273 cred->fsuid = GLOBAL_ROOT_UID; 274 275 scoped_with_creds(cred) 276 return file_open_root(&root, filename, flags, mode); 277 } 278 279 static int sev_read_init_ex_file(void) 280 { 281 struct sev_device *sev = psp_master->sev_data; 282 struct file *fp; 283 ssize_t nread; 284 285 lockdep_assert_held(&sev_cmd_mutex); 286 287 if (!sev_init_ex_buffer) 288 return -EOPNOTSUPP; 289 290 fp = open_file_as_root(init_ex_path, O_RDONLY, 0); 291 if (IS_ERR(fp)) { 292 int ret = PTR_ERR(fp); 293 294 if (ret == -ENOENT) { 295 dev_info(sev->dev, 296 "SEV: %s does not exist and will be created later.\n", 297 init_ex_path); 298 ret = 0; 299 } else { 300 dev_err(sev->dev, 301 "SEV: could not open %s for read, error %d\n", 302 init_ex_path, ret); 303 } 304 return ret; 305 } 306 307 nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL); 308 if (nread != NV_LENGTH) { 309 dev_info(sev->dev, 310 "SEV: could not read %u bytes to non volatile memory area, ret %ld\n", 311 NV_LENGTH, nread); 312 } 313 314 dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread); 315 filp_close(fp, NULL); 316 317 return 0; 318 } 319 320 static int sev_write_init_ex_file(void) 321 { 322 struct sev_device *sev = psp_master->sev_data; 323 struct file *fp; 324 loff_t offset = 0; 325 ssize_t nwrite; 326 327 lockdep_assert_held(&sev_cmd_mutex); 328 329 if (!sev_init_ex_buffer) 330 return 0; 331 332 fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600); 333 if (IS_ERR(fp)) { 334 int ret = PTR_ERR(fp); 335 336 dev_err(sev->dev, 337 "SEV: could not open file for write, error %d\n", 338 ret); 339 return ret; 340 } 341 342 nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset); 343 vfs_fsync(fp, 0); 344 filp_close(fp, NULL); 345 346 if (nwrite != NV_LENGTH) { 347 dev_err(sev->dev, 348 "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n", 349 NV_LENGTH, nwrite); 350 return -EIO; 351 } 352 353 dev_dbg(sev->dev, "SEV: write successful to NV file\n"); 354 355 return 0; 356 } 357 358 static int sev_write_init_ex_file_if_required(int cmd_id) 359 { 360 lockdep_assert_held(&sev_cmd_mutex); 361 362 if (!sev_init_ex_buffer) 363 return 0; 364 365 /* 366 * Only a few platform commands modify the SPI/NV area, but none of the 367 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN, 368 * PEK_CERT_IMPORT, and PDH_GEN do. 369 */ 370 switch (cmd_id) { 371 case SEV_CMD_FACTORY_RESET: 372 case SEV_CMD_INIT_EX: 373 case SEV_CMD_PDH_GEN: 374 case SEV_CMD_PEK_CERT_IMPORT: 375 case SEV_CMD_PEK_GEN: 376 break; 377 default: 378 return 0; 379 } 380 381 return sev_write_init_ex_file(); 382 } 383 384 int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked) 385 { 386 int ret, err, i; 387 388 paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE)); 389 390 for (i = 0; i < npages; i++, paddr += PAGE_SIZE) { 391 struct sev_data_snp_page_reclaim data = {0}; 392 393 data.paddr = paddr; 394 395 if (locked) 396 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); 397 else 398 ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); 399 400 if (ret) 401 goto cleanup; 402 403 ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K); 404 if (ret) 405 goto cleanup; 406 } 407 408 return 0; 409 410 cleanup: 411 /* 412 * If there was a failure reclaiming the page then it is no longer safe 413 * to release it back to the system; leak it instead. 414 */ 415 snp_leak_pages(__phys_to_pfn(paddr), npages - i); 416 return ret; 417 } 418 EXPORT_SYMBOL_GPL(snp_reclaim_pages); 419 420 static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked) 421 { 422 unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; 423 int rc, i; 424 425 for (i = 0; i < npages; i++, pfn++) { 426 rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true); 427 if (rc) 428 goto cleanup; 429 } 430 431 return 0; 432 433 cleanup: 434 /* 435 * Try unrolling the firmware state changes by 436 * reclaiming the pages which were already changed to the 437 * firmware state. 438 */ 439 snp_reclaim_pages(paddr, i, locked); 440 441 return rc; 442 } 443 444 static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked) 445 { 446 unsigned long npages = 1ul << order, paddr; 447 struct sev_device *sev; 448 struct page *page; 449 450 if (!psp_master || !psp_master->sev_data) 451 return NULL; 452 453 page = alloc_pages(gfp_mask, order); 454 if (!page) 455 return NULL; 456 457 /* If SEV-SNP is initialized then add the page in RMP table. */ 458 sev = psp_master->sev_data; 459 if (!sev->snp_initialized) 460 return page; 461 462 paddr = __pa((unsigned long)page_address(page)); 463 if (rmp_mark_pages_firmware(paddr, npages, locked)) 464 return NULL; 465 466 return page; 467 } 468 469 void *snp_alloc_firmware_page(gfp_t gfp_mask) 470 { 471 struct page *page; 472 473 page = __snp_alloc_firmware_pages(gfp_mask, 0, false); 474 475 return page ? page_address(page) : NULL; 476 } 477 EXPORT_SYMBOL_GPL(snp_alloc_firmware_page); 478 479 static void __snp_free_firmware_pages(struct page *page, int order, bool locked) 480 { 481 struct sev_device *sev = psp_master->sev_data; 482 unsigned long paddr, npages = 1ul << order; 483 484 if (!page) 485 return; 486 487 paddr = __pa((unsigned long)page_address(page)); 488 if (sev->snp_initialized && 489 snp_reclaim_pages(paddr, npages, locked)) 490 return; 491 492 __free_pages(page, order); 493 } 494 495 void snp_free_firmware_page(void *addr) 496 { 497 if (!addr) 498 return; 499 500 __snp_free_firmware_pages(virt_to_page(addr), 0, false); 501 } 502 EXPORT_SYMBOL_GPL(snp_free_firmware_page); 503 504 static void *sev_fw_alloc(unsigned long len) 505 { 506 struct page *page; 507 508 page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true); 509 if (!page) 510 return NULL; 511 512 return page_address(page); 513 } 514 515 /** 516 * struct cmd_buf_desc - descriptors for managing legacy SEV command address 517 * parameters corresponding to buffers that may be written to by firmware. 518 * 519 * @paddr_ptr: pointer to the address parameter in the command buffer which may 520 * need to be saved/restored depending on whether a bounce buffer 521 * is used. In the case of a bounce buffer, the command buffer 522 * needs to be updated with the address of the new bounce buffer 523 * snp_map_cmd_buf_desc() has allocated specifically for it. Must 524 * be NULL if this descriptor is only an end-of-list indicator. 525 * 526 * @paddr_orig: storage for the original address parameter, which can be used to 527 * restore the original value in @paddr_ptr in cases where it is 528 * replaced with the address of a bounce buffer. 529 * 530 * @len: length of buffer located at the address originally stored at @paddr_ptr 531 * 532 * @guest_owned: true if the address corresponds to guest-owned pages, in which 533 * case bounce buffers are not needed. 534 */ 535 struct cmd_buf_desc { 536 u64 *paddr_ptr; 537 u64 paddr_orig; 538 u32 len; 539 bool guest_owned; 540 }; 541 542 /* 543 * If a legacy SEV command parameter is a memory address, those pages in 544 * turn need to be transitioned to/from firmware-owned before/after 545 * executing the firmware command. 546 * 547 * Additionally, in cases where those pages are not guest-owned, a bounce 548 * buffer is needed in place of the original memory address parameter. 549 * 550 * A set of descriptors are used to keep track of this handling, and 551 * initialized here based on the specific commands being executed. 552 */ 553 static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf, 554 struct cmd_buf_desc *desc_list) 555 { 556 switch (cmd) { 557 case SEV_CMD_PDH_CERT_EXPORT: { 558 struct sev_data_pdh_cert_export *data = cmd_buf; 559 560 desc_list[0].paddr_ptr = &data->pdh_cert_address; 561 desc_list[0].len = data->pdh_cert_len; 562 desc_list[1].paddr_ptr = &data->cert_chain_address; 563 desc_list[1].len = data->cert_chain_len; 564 break; 565 } 566 case SEV_CMD_GET_ID: { 567 struct sev_data_get_id *data = cmd_buf; 568 569 desc_list[0].paddr_ptr = &data->address; 570 desc_list[0].len = data->len; 571 break; 572 } 573 case SEV_CMD_PEK_CSR: { 574 struct sev_data_pek_csr *data = cmd_buf; 575 576 desc_list[0].paddr_ptr = &data->address; 577 desc_list[0].len = data->len; 578 break; 579 } 580 case SEV_CMD_LAUNCH_UPDATE_DATA: { 581 struct sev_data_launch_update_data *data = cmd_buf; 582 583 desc_list[0].paddr_ptr = &data->address; 584 desc_list[0].len = data->len; 585 desc_list[0].guest_owned = true; 586 break; 587 } 588 case SEV_CMD_LAUNCH_UPDATE_VMSA: { 589 struct sev_data_launch_update_vmsa *data = cmd_buf; 590 591 desc_list[0].paddr_ptr = &data->address; 592 desc_list[0].len = data->len; 593 desc_list[0].guest_owned = true; 594 break; 595 } 596 case SEV_CMD_LAUNCH_MEASURE: { 597 struct sev_data_launch_measure *data = cmd_buf; 598 599 desc_list[0].paddr_ptr = &data->address; 600 desc_list[0].len = data->len; 601 break; 602 } 603 case SEV_CMD_LAUNCH_UPDATE_SECRET: { 604 struct sev_data_launch_secret *data = cmd_buf; 605 606 desc_list[0].paddr_ptr = &data->guest_address; 607 desc_list[0].len = data->guest_len; 608 desc_list[0].guest_owned = true; 609 break; 610 } 611 case SEV_CMD_DBG_DECRYPT: { 612 struct sev_data_dbg *data = cmd_buf; 613 614 desc_list[0].paddr_ptr = &data->dst_addr; 615 desc_list[0].len = data->len; 616 desc_list[0].guest_owned = true; 617 break; 618 } 619 case SEV_CMD_DBG_ENCRYPT: { 620 struct sev_data_dbg *data = cmd_buf; 621 622 desc_list[0].paddr_ptr = &data->dst_addr; 623 desc_list[0].len = data->len; 624 desc_list[0].guest_owned = true; 625 break; 626 } 627 case SEV_CMD_ATTESTATION_REPORT: { 628 struct sev_data_attestation_report *data = cmd_buf; 629 630 desc_list[0].paddr_ptr = &data->address; 631 desc_list[0].len = data->len; 632 break; 633 } 634 case SEV_CMD_SEND_START: { 635 struct sev_data_send_start *data = cmd_buf; 636 637 desc_list[0].paddr_ptr = &data->session_address; 638 desc_list[0].len = data->session_len; 639 break; 640 } 641 case SEV_CMD_SEND_UPDATE_DATA: { 642 struct sev_data_send_update_data *data = cmd_buf; 643 644 desc_list[0].paddr_ptr = &data->hdr_address; 645 desc_list[0].len = data->hdr_len; 646 desc_list[1].paddr_ptr = &data->trans_address; 647 desc_list[1].len = data->trans_len; 648 break; 649 } 650 case SEV_CMD_SEND_UPDATE_VMSA: { 651 struct sev_data_send_update_vmsa *data = cmd_buf; 652 653 desc_list[0].paddr_ptr = &data->hdr_address; 654 desc_list[0].len = data->hdr_len; 655 desc_list[1].paddr_ptr = &data->trans_address; 656 desc_list[1].len = data->trans_len; 657 break; 658 } 659 case SEV_CMD_RECEIVE_UPDATE_DATA: { 660 struct sev_data_receive_update_data *data = cmd_buf; 661 662 desc_list[0].paddr_ptr = &data->guest_address; 663 desc_list[0].len = data->guest_len; 664 desc_list[0].guest_owned = true; 665 break; 666 } 667 case SEV_CMD_RECEIVE_UPDATE_VMSA: { 668 struct sev_data_receive_update_vmsa *data = cmd_buf; 669 670 desc_list[0].paddr_ptr = &data->guest_address; 671 desc_list[0].len = data->guest_len; 672 desc_list[0].guest_owned = true; 673 break; 674 } 675 default: 676 break; 677 } 678 } 679 680 static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc) 681 { 682 unsigned int npages; 683 684 if (!desc->len) 685 return 0; 686 687 /* Allocate a bounce buffer if this isn't a guest owned page. */ 688 if (!desc->guest_owned) { 689 struct page *page; 690 691 page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len)); 692 if (!page) { 693 pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n"); 694 return -ENOMEM; 695 } 696 697 desc->paddr_orig = *desc->paddr_ptr; 698 *desc->paddr_ptr = __psp_pa(page_to_virt(page)); 699 } 700 701 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; 702 703 /* Transition the buffer to firmware-owned. */ 704 if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) { 705 pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n"); 706 return -EFAULT; 707 } 708 709 return 0; 710 } 711 712 static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc) 713 { 714 unsigned int npages; 715 716 if (!desc->len) 717 return 0; 718 719 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; 720 721 /* Transition the buffers back to hypervisor-owned. */ 722 if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) { 723 pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n"); 724 return -EFAULT; 725 } 726 727 /* Copy data from bounce buffer and then free it. */ 728 if (!desc->guest_owned) { 729 void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr)); 730 void *dst_buf = __va(__sme_clr(desc->paddr_orig)); 731 732 memcpy(dst_buf, bounce_buf, desc->len); 733 __free_pages(virt_to_page(bounce_buf), get_order(desc->len)); 734 735 /* Restore the original address in the command buffer. */ 736 *desc->paddr_ptr = desc->paddr_orig; 737 } 738 739 return 0; 740 } 741 742 static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) 743 { 744 int i; 745 746 snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list); 747 748 for (i = 0; i < CMD_BUF_DESC_MAX; i++) { 749 struct cmd_buf_desc *desc = &desc_list[i]; 750 751 if (!desc->paddr_ptr) 752 break; 753 754 if (snp_map_cmd_buf_desc(desc)) 755 goto err_unmap; 756 } 757 758 return 0; 759 760 err_unmap: 761 for (i--; i >= 0; i--) 762 snp_unmap_cmd_buf_desc(&desc_list[i]); 763 764 return -EFAULT; 765 } 766 767 static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list) 768 { 769 int i, ret = 0; 770 771 for (i = 0; i < CMD_BUF_DESC_MAX; i++) { 772 struct cmd_buf_desc *desc = &desc_list[i]; 773 774 if (!desc->paddr_ptr) 775 break; 776 777 if (snp_unmap_cmd_buf_desc(&desc_list[i])) 778 ret = -EFAULT; 779 } 780 781 return ret; 782 } 783 784 static bool sev_cmd_buf_writable(int cmd) 785 { 786 switch (cmd) { 787 case SEV_CMD_PLATFORM_STATUS: 788 case SEV_CMD_GUEST_STATUS: 789 case SEV_CMD_LAUNCH_START: 790 case SEV_CMD_RECEIVE_START: 791 case SEV_CMD_LAUNCH_MEASURE: 792 case SEV_CMD_SEND_START: 793 case SEV_CMD_SEND_UPDATE_DATA: 794 case SEV_CMD_SEND_UPDATE_VMSA: 795 case SEV_CMD_PEK_CSR: 796 case SEV_CMD_PDH_CERT_EXPORT: 797 case SEV_CMD_GET_ID: 798 case SEV_CMD_ATTESTATION_REPORT: 799 return true; 800 default: 801 return false; 802 } 803 } 804 805 /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */ 806 static bool snp_legacy_handling_needed(int cmd) 807 { 808 struct sev_device *sev = psp_master->sev_data; 809 810 return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized; 811 } 812 813 static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) 814 { 815 if (!snp_legacy_handling_needed(cmd)) 816 return 0; 817 818 if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list)) 819 return -EFAULT; 820 821 /* 822 * Before command execution, the command buffer needs to be put into 823 * the firmware-owned state. 824 */ 825 if (sev_cmd_buf_writable(cmd)) { 826 if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true)) 827 return -EFAULT; 828 } 829 830 return 0; 831 } 832 833 static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf) 834 { 835 if (!snp_legacy_handling_needed(cmd)) 836 return 0; 837 838 /* 839 * After command completion, the command buffer needs to be put back 840 * into the hypervisor-owned state. 841 */ 842 if (sev_cmd_buf_writable(cmd)) 843 if (snp_reclaim_pages(__pa(cmd_buf), 1, true)) 844 return -EFAULT; 845 846 return 0; 847 } 848 849 int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) 850 { 851 struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0}; 852 struct psp_device *psp = psp_master; 853 struct sev_device *sev; 854 unsigned int cmdbuff_hi, cmdbuff_lo; 855 unsigned int phys_lsb, phys_msb; 856 unsigned int reg; 857 void *cmd_buf; 858 int buf_len; 859 int ret = 0; 860 861 if (!psp || !psp->sev_data) 862 return -ENODEV; 863 864 if (psp_dead) 865 return -EBUSY; 866 867 sev = psp->sev_data; 868 869 buf_len = sev_cmd_buffer_len(cmd); 870 if (WARN_ON_ONCE(!data != !buf_len)) 871 return -EINVAL; 872 873 /* 874 * Copy the incoming data to driver's scratch buffer as __pa() will not 875 * work for some memory, e.g. vmalloc'd addresses, and @data may not be 876 * physically contiguous. 877 */ 878 if (data) { 879 /* 880 * Commands are generally issued one at a time and require the 881 * sev_cmd_mutex, but there could be recursive firmware requests 882 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while 883 * preparing buffers for another command. This is the only known 884 * case of nesting in the current code, so exactly one 885 * additional command buffer is available for that purpose. 886 */ 887 if (!sev->cmd_buf_active) { 888 cmd_buf = sev->cmd_buf; 889 sev->cmd_buf_active = true; 890 } else if (!sev->cmd_buf_backup_active) { 891 cmd_buf = sev->cmd_buf_backup; 892 sev->cmd_buf_backup_active = true; 893 } else { 894 dev_err(sev->dev, 895 "SEV: too many firmware commands in progress, no command buffers available.\n"); 896 return -EBUSY; 897 } 898 899 memcpy(cmd_buf, data, buf_len); 900 901 /* 902 * The behavior of the SEV-legacy commands is altered when the 903 * SNP firmware is in the INIT state. 904 */ 905 ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list); 906 if (ret) { 907 dev_err(sev->dev, 908 "SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n", 909 cmd, ret); 910 return ret; 911 } 912 } else { 913 cmd_buf = sev->cmd_buf; 914 } 915 916 /* Get the physical address of the command buffer */ 917 phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0; 918 phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0; 919 920 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n", 921 cmd, phys_msb, phys_lsb, psp_timeout); 922 923 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, 924 buf_len, false); 925 926 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 927 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 928 929 sev->int_rcvd = 0; 930 931 reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd); 932 933 /* 934 * If invoked during panic handling, local interrupts are disabled so 935 * the PSP command completion interrupt can't be used. 936 * sev_wait_cmd_ioc() already checks for interrupts disabled and 937 * polls for PSP command completion. Ensure we do not request an 938 * interrupt from the PSP if irqs disabled. 939 */ 940 if (!irqs_disabled()) 941 reg |= SEV_CMDRESP_IOC; 942 943 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); 944 945 /* wait for command completion */ 946 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout); 947 if (ret) { 948 if (psp_ret) 949 *psp_ret = 0; 950 951 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd); 952 psp_dead = true; 953 954 return ret; 955 } 956 957 psp_timeout = psp_cmd_timeout; 958 959 if (psp_ret) 960 *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg); 961 962 if (FIELD_GET(PSP_CMDRESP_STS, reg)) { 963 dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n", 964 cmd, FIELD_GET(PSP_CMDRESP_STS, reg)); 965 966 /* 967 * PSP firmware may report additional error information in the 968 * command buffer registers on error. Print contents of command 969 * buffer registers if they changed. 970 */ 971 cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 972 cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 973 if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) { 974 dev_dbg(sev->dev, "Additional error information reported in cmdbuff:"); 975 dev_dbg(sev->dev, " cmdbuff hi: %#010x\n", cmdbuff_hi); 976 dev_dbg(sev->dev, " cmdbuff lo: %#010x\n", cmdbuff_lo); 977 } 978 ret = -EIO; 979 } else { 980 ret = sev_write_init_ex_file_if_required(cmd); 981 } 982 983 /* 984 * Copy potential output from the PSP back to data. Do this even on 985 * failure in case the caller wants to glean something from the error. 986 */ 987 if (data) { 988 int ret_reclaim; 989 /* 990 * Restore the page state after the command completes. 991 */ 992 ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf); 993 if (ret_reclaim) { 994 dev_err(sev->dev, 995 "SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n", 996 cmd, ret_reclaim); 997 return ret_reclaim; 998 } 999 1000 memcpy(data, cmd_buf, buf_len); 1001 1002 if (sev->cmd_buf_backup_active) 1003 sev->cmd_buf_backup_active = false; 1004 else 1005 sev->cmd_buf_active = false; 1006 1007 if (snp_unmap_cmd_buf_desc_list(desc_list)) 1008 return -EFAULT; 1009 } 1010 1011 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, 1012 buf_len, false); 1013 1014 return ret; 1015 } 1016 1017 int sev_do_cmd(int cmd, void *data, int *psp_ret) 1018 { 1019 int rc; 1020 1021 mutex_lock(&sev_cmd_mutex); 1022 rc = __sev_do_cmd_locked(cmd, data, psp_ret); 1023 mutex_unlock(&sev_cmd_mutex); 1024 1025 return rc; 1026 } 1027 EXPORT_SYMBOL_GPL(sev_do_cmd); 1028 1029 static int __sev_init_locked(int *error) 1030 { 1031 struct sev_data_init data; 1032 1033 memset(&data, 0, sizeof(data)); 1034 if (sev_es_tmr) { 1035 /* 1036 * Do not include the encryption mask on the physical 1037 * address of the TMR (firmware should clear it anyway). 1038 */ 1039 data.tmr_address = __pa(sev_es_tmr); 1040 1041 data.flags |= SEV_INIT_FLAGS_SEV_ES; 1042 data.tmr_len = sev_es_tmr_size; 1043 } 1044 1045 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); 1046 } 1047 1048 static int __sev_init_ex_locked(int *error) 1049 { 1050 struct sev_data_init_ex data; 1051 1052 memset(&data, 0, sizeof(data)); 1053 data.length = sizeof(data); 1054 data.nv_address = __psp_pa(sev_init_ex_buffer); 1055 data.nv_len = NV_LENGTH; 1056 1057 if (sev_es_tmr) { 1058 /* 1059 * Do not include the encryption mask on the physical 1060 * address of the TMR (firmware should clear it anyway). 1061 */ 1062 data.tmr_address = __pa(sev_es_tmr); 1063 1064 data.flags |= SEV_INIT_FLAGS_SEV_ES; 1065 data.tmr_len = sev_es_tmr_size; 1066 } 1067 1068 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); 1069 } 1070 1071 static inline int __sev_do_init_locked(int *psp_ret) 1072 { 1073 if (sev_init_ex_buffer) 1074 return __sev_init_ex_locked(psp_ret); 1075 else 1076 return __sev_init_locked(psp_ret); 1077 } 1078 1079 /* Hypervisor Fixed pages API interface */ 1080 static void snp_hv_fixed_pages_state_update(struct sev_device *sev, 1081 enum snp_hv_fixed_pages_state page_state) 1082 { 1083 struct snp_hv_fixed_pages_entry *entry; 1084 1085 /* List is protected by sev_cmd_mutex */ 1086 lockdep_assert_held(&sev_cmd_mutex); 1087 1088 if (list_empty(&snp_hv_fixed_pages)) 1089 return; 1090 1091 list_for_each_entry(entry, &snp_hv_fixed_pages, list) 1092 entry->page_state = page_state; 1093 } 1094 1095 /* 1096 * Allocate HV_FIXED pages in 2MB aligned sizes to ensure the whole 1097 * 2MB pages are marked as HV_FIXED. 1098 */ 1099 struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages) 1100 { 1101 struct psp_device *psp_master = psp_get_master_device(); 1102 struct snp_hv_fixed_pages_entry *entry; 1103 unsigned int order; 1104 struct page *page; 1105 1106 if (!psp_master) 1107 return NULL; 1108 1109 order = get_order(PMD_SIZE * num_2mb_pages); 1110 1111 /* 1112 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list 1113 * also needs to be protected using the same mutex. 1114 */ 1115 guard(mutex)(&sev_cmd_mutex); 1116 1117 /* 1118 * This API uses SNP_INIT_EX to transition allocated pages to HV_Fixed 1119 * page state, fail if SNP is already initialized. 1120 */ 1121 if (psp_master->sev_data && 1122 ((struct sev_device *)psp_master->sev_data)->snp_initialized) 1123 return NULL; 1124 1125 /* Re-use freed pages that match the request */ 1126 list_for_each_entry(entry, &snp_hv_fixed_pages, list) { 1127 /* Hypervisor fixed page allocator implements exact fit policy */ 1128 if (entry->order == order && entry->free) { 1129 entry->free = false; 1130 memset(page_address(entry->page), 0, 1131 (1 << entry->order) * PAGE_SIZE); 1132 return entry->page; 1133 } 1134 } 1135 1136 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); 1137 if (!page) 1138 return NULL; 1139 1140 entry = kzalloc_obj(*entry); 1141 if (!entry) { 1142 __free_pages(page, order); 1143 return NULL; 1144 } 1145 1146 entry->page = page; 1147 entry->order = order; 1148 list_add_tail(&entry->list, &snp_hv_fixed_pages); 1149 1150 return page; 1151 } 1152 1153 void snp_free_hv_fixed_pages(struct page *page) 1154 { 1155 struct psp_device *psp_master = psp_get_master_device(); 1156 struct snp_hv_fixed_pages_entry *entry, *nentry; 1157 1158 if (!psp_master) 1159 return; 1160 1161 /* 1162 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list 1163 * also needs to be protected using the same mutex. 1164 */ 1165 guard(mutex)(&sev_cmd_mutex); 1166 1167 list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) { 1168 if (entry->page != page) 1169 continue; 1170 1171 /* 1172 * HV_FIXED page state cannot be changed until reboot 1173 * and they cannot be used by an SNP guest, so they cannot 1174 * be returned back to the page allocator. 1175 * Mark the pages as free internally to allow possible re-use. 1176 */ 1177 if (entry->page_state == HV_FIXED) { 1178 entry->free = true; 1179 } else { 1180 __free_pages(page, entry->order); 1181 list_del(&entry->list); 1182 kfree(entry); 1183 } 1184 return; 1185 } 1186 } 1187 1188 static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range_list *range_list) 1189 { 1190 struct snp_hv_fixed_pages_entry *entry; 1191 struct sev_data_range *range; 1192 int num_elements; 1193 1194 lockdep_assert_held(&sev_cmd_mutex); 1195 1196 if (list_empty(&snp_hv_fixed_pages)) 1197 return; 1198 1199 num_elements = list_count_nodes(&snp_hv_fixed_pages) + 1200 range_list->num_elements; 1201 1202 /* 1203 * Ensure the list of HV_FIXED pages that will be passed to firmware 1204 * do not exceed the page-sized argument buffer. 1205 */ 1206 if (num_elements * sizeof(*range) + sizeof(*range_list) > PAGE_SIZE) { 1207 dev_warn(sev->dev, "Additional HV_Fixed pages cannot be accommodated, omitting\n"); 1208 return; 1209 } 1210 1211 range = &range_list->ranges[range_list->num_elements]; 1212 list_for_each_entry(entry, &snp_hv_fixed_pages, list) { 1213 range->base = page_to_pfn(entry->page) << PAGE_SHIFT; 1214 range->page_count = 1 << entry->order; 1215 range++; 1216 } 1217 range_list->num_elements = num_elements; 1218 } 1219 1220 static void snp_leak_hv_fixed_pages(void) 1221 { 1222 struct snp_hv_fixed_pages_entry *entry, *nentry; 1223 1224 /* List is protected by sev_cmd_mutex */ 1225 lockdep_assert_held(&sev_cmd_mutex); 1226 1227 if (list_empty(&snp_hv_fixed_pages)) 1228 return; 1229 1230 list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) { 1231 if (entry->free && entry->page_state != HV_FIXED) 1232 __free_pages(entry->page, entry->order); 1233 else 1234 __snp_leak_pages(page_to_pfn(entry->page), 1235 1 << entry->order, false); 1236 1237 list_del(&entry->list); 1238 kfree(entry); 1239 } 1240 } 1241 1242 bool sev_is_snp_ciphertext_hiding_supported(void) 1243 { 1244 struct psp_device *psp = psp_master; 1245 struct sev_device *sev; 1246 1247 if (!psp || !psp->sev_data) 1248 return false; 1249 1250 sev = psp->sev_data; 1251 1252 /* 1253 * Feature information indicates if CipherTextHiding feature is 1254 * supported by the SEV firmware and additionally platform status 1255 * indicates if CipherTextHiding feature is enabled in the 1256 * Platform BIOS. 1257 */ 1258 return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) && 1259 sev->snp_plat_status.ciphertext_hiding_cap); 1260 } 1261 EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported); 1262 1263 static int snp_get_platform_data(struct sev_device *sev, int *error) 1264 { 1265 struct sev_data_snp_feature_info snp_feat_info; 1266 struct snp_feature_info *feat_info; 1267 struct sev_data_snp_addr buf; 1268 struct page *page; 1269 int rc; 1270 1271 /* 1272 * This function is expected to be called before SNP is 1273 * initialized. 1274 */ 1275 if (sev->snp_initialized) 1276 return -EINVAL; 1277 1278 buf.address = __psp_pa(&sev->snp_plat_status); 1279 rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error); 1280 if (rc) { 1281 dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n", 1282 rc, *error); 1283 return rc; 1284 } 1285 1286 sev->api_major = sev->snp_plat_status.api_major; 1287 sev->api_minor = sev->snp_plat_status.api_minor; 1288 sev->build = sev->snp_plat_status.build_id; 1289 1290 /* 1291 * Do feature discovery of the currently loaded firmware, 1292 * and cache feature information from CPUID 0x8000_0024, 1293 * sub-function 0. 1294 */ 1295 if (!sev->snp_plat_status.feature_info) 1296 return 0; 1297 1298 /* 1299 * Use dynamically allocated structure for the SNP_FEATURE_INFO 1300 * command to ensure structure is 8-byte aligned, and does not 1301 * cross a page boundary. 1302 */ 1303 page = alloc_page(GFP_KERNEL); 1304 if (!page) 1305 return -ENOMEM; 1306 1307 feat_info = page_address(page); 1308 snp_feat_info.length = sizeof(snp_feat_info); 1309 snp_feat_info.ecx_in = 0; 1310 snp_feat_info.feature_info_paddr = __psp_pa(feat_info); 1311 1312 rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error); 1313 if (!rc) 1314 sev->snp_feat_info_0 = *feat_info; 1315 else 1316 dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n", 1317 rc, *error); 1318 1319 __free_page(page); 1320 1321 return rc; 1322 } 1323 1324 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg) 1325 { 1326 struct sev_data_range_list *range_list = arg; 1327 struct sev_data_range *range = &range_list->ranges[range_list->num_elements]; 1328 size_t size; 1329 1330 /* 1331 * Ensure the list of HV_FIXED pages that will be passed to firmware 1332 * do not exceed the page-sized argument buffer. 1333 */ 1334 if ((range_list->num_elements * sizeof(struct sev_data_range) + 1335 sizeof(struct sev_data_range_list)) > PAGE_SIZE) 1336 return -E2BIG; 1337 1338 switch (rs->desc) { 1339 case E820_TYPE_RESERVED: 1340 case E820_TYPE_PMEM: 1341 case E820_TYPE_ACPI: 1342 range->base = rs->start & PAGE_MASK; 1343 size = PAGE_ALIGN((rs->end + 1) - rs->start); 1344 range->page_count = size >> PAGE_SHIFT; 1345 range_list->num_elements++; 1346 break; 1347 default: 1348 break; 1349 } 1350 1351 return 0; 1352 } 1353 1354 static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid) 1355 { 1356 struct sev_data_range_list *snp_range_list __free(kfree) = NULL; 1357 struct psp_device *psp = psp_master; 1358 struct sev_data_snp_init_ex data; 1359 struct sev_device *sev; 1360 void *arg = &data; 1361 int cmd, rc = 0; 1362 1363 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) 1364 return -ENODEV; 1365 1366 sev = psp->sev_data; 1367 1368 if (sev->snp_initialized) 1369 return 0; 1370 1371 if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) { 1372 dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n", 1373 SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR); 1374 return -EOPNOTSUPP; 1375 } 1376 1377 snp_prepare(); 1378 1379 /* 1380 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list 1381 * of system physical address ranges to convert into HV-fixed page 1382 * states during the RMP initialization. For instance, the memory that 1383 * UEFI reserves should be included in the that list. This allows system 1384 * components that occasionally write to memory (e.g. logging to UEFI 1385 * reserved regions) to not fail due to RMP initialization and SNP 1386 * enablement. 1387 * 1388 */ 1389 if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) { 1390 bool tio_supp = !!(sev->snp_feat_info_0.ebx & SNP_SEV_TIO_SUPPORTED); 1391 1392 /* 1393 * Firmware checks that the pages containing the ranges enumerated 1394 * in the RANGES structure are either in the default page state or in the 1395 * firmware page state. 1396 */ 1397 snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL); 1398 if (!snp_range_list) { 1399 dev_err(sev->dev, 1400 "SEV: SNP_INIT_EX range list memory allocation failed\n"); 1401 return -ENOMEM; 1402 } 1403 1404 /* 1405 * Retrieve all reserved memory regions from the e820 memory map 1406 * to be setup as HV-fixed pages. 1407 */ 1408 rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0, 1409 snp_range_list, snp_filter_reserved_mem_regions); 1410 if (rc) { 1411 dev_err(sev->dev, 1412 "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc); 1413 return rc; 1414 } 1415 1416 /* 1417 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the 1418 * HV_Fixed page list. 1419 */ 1420 snp_add_hv_fixed_pages(sev, snp_range_list); 1421 1422 memset(&data, 0, sizeof(data)); 1423 1424 if (max_snp_asid) { 1425 data.ciphertext_hiding_en = 1; 1426 data.max_snp_asid = max_snp_asid; 1427 } 1428 1429 data.init_rmp = 1; 1430 data.list_paddr_en = 1; 1431 data.list_paddr = __psp_pa(snp_range_list); 1432 1433 data.tio_en = tio_supp && sev_tio_enabled && amd_iommu_sev_tio_supported(); 1434 1435 /* 1436 * When psp_init_on_probe is disabled, the userspace calling 1437 * SEV ioctl can inadvertently shut down SNP and SEV-TIO causing 1438 * unexpected state loss. 1439 */ 1440 if (data.tio_en && !psp_init_on_probe) 1441 dev_warn(sev->dev, "SEV-TIO as incompatible with psp_init_on_probe=0\n"); 1442 1443 cmd = SEV_CMD_SNP_INIT_EX; 1444 } else { 1445 cmd = SEV_CMD_SNP_INIT; 1446 arg = NULL; 1447 } 1448 1449 /* 1450 * The following sequence must be issued before launching the first SNP 1451 * guest to ensure all dirty cache lines are flushed, including from 1452 * updates to the RMP table itself via the RMPUPDATE instruction: 1453 * 1454 * - WBINVD on all running CPUs 1455 * - SEV_CMD_SNP_INIT[_EX] firmware command 1456 * - WBINVD on all running CPUs 1457 * - SEV_CMD_SNP_DF_FLUSH firmware command 1458 */ 1459 wbinvd_on_all_cpus(); 1460 1461 rc = __sev_do_cmd_locked(cmd, arg, error); 1462 if (rc) { 1463 dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n", 1464 cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT", 1465 rc, *error); 1466 return rc; 1467 } 1468 1469 /* Prepare for first SNP guest launch after INIT. */ 1470 wbinvd_on_all_cpus(); 1471 rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error); 1472 if (rc) { 1473 dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n", 1474 rc, *error); 1475 return rc; 1476 } 1477 1478 snp_hv_fixed_pages_state_update(sev, HV_FIXED); 1479 sev->snp_initialized = true; 1480 dev_dbg(sev->dev, "SEV-SNP firmware initialized, SEV-TIO is %s\n", 1481 data.tio_en ? "enabled" : "disabled"); 1482 1483 dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major, 1484 sev->api_minor, sev->build); 1485 1486 atomic_notifier_chain_register(&panic_notifier_list, 1487 &snp_panic_notifier); 1488 1489 if (data.tio_en) { 1490 /* 1491 * This executes with the sev_cmd_mutex held so down the stack 1492 * snp_reclaim_pages(locked=false) might be needed (which is extremely 1493 * unlikely) but will cause a deadlock. 1494 * Instead of exporting __snp_alloc_firmware_pages(), allocate a page 1495 * for this one call here. 1496 */ 1497 void *tio_status = page_address(__snp_alloc_firmware_pages( 1498 GFP_KERNEL_ACCOUNT | __GFP_ZERO, 0, true)); 1499 1500 if (tio_status) { 1501 sev_tsm_init_locked(sev, tio_status); 1502 __snp_free_firmware_pages(virt_to_page(tio_status), 0, true); 1503 } 1504 } 1505 1506 sev_es_tmr_size = SNP_TMR_SIZE; 1507 1508 return 0; 1509 } 1510 1511 static void __sev_platform_init_handle_tmr(struct sev_device *sev) 1512 { 1513 if (sev_es_tmr) 1514 return; 1515 1516 /* Obtain the TMR memory area for SEV-ES use */ 1517 sev_es_tmr = sev_fw_alloc(sev_es_tmr_size); 1518 if (sev_es_tmr) { 1519 /* Must flush the cache before giving it to the firmware */ 1520 if (!sev->snp_initialized) 1521 clflush_cache_range(sev_es_tmr, sev_es_tmr_size); 1522 } else { 1523 dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n"); 1524 } 1525 } 1526 1527 /* 1528 * If an init_ex_path is provided allocate a buffer for the file and 1529 * read in the contents. Additionally, if SNP is initialized, convert 1530 * the buffer pages to firmware pages. 1531 */ 1532 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev) 1533 { 1534 struct page *page; 1535 int rc; 1536 1537 if (!init_ex_path) 1538 return 0; 1539 1540 if (sev_init_ex_buffer) 1541 return 0; 1542 1543 page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH)); 1544 if (!page) { 1545 dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n"); 1546 return -ENOMEM; 1547 } 1548 1549 sev_init_ex_buffer = page_address(page); 1550 1551 rc = sev_read_init_ex_file(); 1552 if (rc) 1553 return rc; 1554 1555 /* If SEV-SNP is initialized, transition to firmware page. */ 1556 if (sev->snp_initialized) { 1557 unsigned long npages; 1558 1559 npages = 1UL << get_order(NV_LENGTH); 1560 if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) { 1561 dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n"); 1562 return -ENOMEM; 1563 } 1564 } 1565 1566 return 0; 1567 } 1568 1569 static int __sev_platform_init_locked(int *error) 1570 { 1571 int rc, psp_ret, dfflush_error; 1572 struct sev_device *sev; 1573 1574 psp_ret = dfflush_error = SEV_RET_NO_FW_CALL; 1575 1576 if (!psp_master || !psp_master->sev_data) 1577 return -ENODEV; 1578 1579 sev = psp_master->sev_data; 1580 1581 if (sev->sev_plat_status.state == SEV_STATE_INIT) 1582 return 0; 1583 1584 __sev_platform_init_handle_tmr(sev); 1585 1586 rc = __sev_platform_init_handle_init_ex_path(sev); 1587 if (rc) 1588 return rc; 1589 1590 rc = __sev_do_init_locked(&psp_ret); 1591 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { 1592 /* 1593 * Initialization command returned an integrity check failure 1594 * status code, meaning that firmware load and validation of SEV 1595 * related persistent data has failed. Retrying the 1596 * initialization function should succeed by replacing the state 1597 * with a reset state. 1598 */ 1599 dev_err(sev->dev, 1600 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state."); 1601 rc = __sev_do_init_locked(&psp_ret); 1602 } 1603 1604 if (error) 1605 *error = psp_ret; 1606 1607 if (rc) { 1608 dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n", 1609 sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc); 1610 return rc; 1611 } 1612 1613 sev->sev_plat_status.state = SEV_STATE_INIT; 1614 1615 /* Prepare for first SEV guest launch after INIT */ 1616 wbinvd_on_all_cpus(); 1617 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error); 1618 if (rc) { 1619 dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n", 1620 dfflush_error, rc); 1621 return rc; 1622 } 1623 1624 dev_dbg(sev->dev, "SEV firmware initialized\n"); 1625 1626 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, 1627 sev->api_minor, sev->build); 1628 1629 return 0; 1630 } 1631 1632 static int _sev_platform_init_locked(struct sev_platform_init_args *args) 1633 { 1634 struct sev_device *sev; 1635 int rc; 1636 1637 if (!psp_master || !psp_master->sev_data) 1638 return -ENODEV; 1639 1640 /* 1641 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP 1642 * may already be initialized in the previous kernel. Since no 1643 * SNP/SEV guests are run under a kdump kernel, there is no 1644 * need to initialize SNP or SEV during kdump boot. 1645 */ 1646 if (is_kdump_kernel()) 1647 return 0; 1648 1649 sev = psp_master->sev_data; 1650 1651 if (sev->sev_plat_status.state == SEV_STATE_INIT) 1652 return 0; 1653 1654 rc = __sev_snp_init_locked(&args->error, args->max_snp_asid); 1655 if (rc && rc != -ENODEV) 1656 return rc; 1657 1658 /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */ 1659 if (args->probe && !psp_init_on_probe) 1660 return 0; 1661 1662 return __sev_platform_init_locked(&args->error); 1663 } 1664 1665 int sev_platform_init(struct sev_platform_init_args *args) 1666 { 1667 int rc; 1668 1669 mutex_lock(&sev_cmd_mutex); 1670 rc = _sev_platform_init_locked(args); 1671 mutex_unlock(&sev_cmd_mutex); 1672 1673 return rc; 1674 } 1675 EXPORT_SYMBOL_GPL(sev_platform_init); 1676 1677 static int __sev_platform_shutdown_locked(int *error) 1678 { 1679 struct psp_device *psp = psp_master; 1680 struct sev_device *sev; 1681 int ret; 1682 1683 if (!psp || !psp->sev_data) 1684 return 0; 1685 1686 sev = psp->sev_data; 1687 1688 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) 1689 return 0; 1690 1691 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error); 1692 if (ret) { 1693 dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n", 1694 *error, ret); 1695 return ret; 1696 } 1697 1698 sev->sev_plat_status.state = SEV_STATE_UNINIT; 1699 dev_dbg(sev->dev, "SEV firmware shutdown\n"); 1700 1701 return ret; 1702 } 1703 1704 static int sev_get_platform_state(int *state, int *error) 1705 { 1706 struct sev_user_data_status data; 1707 int rc; 1708 1709 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error); 1710 if (rc) 1711 return rc; 1712 1713 *state = data.state; 1714 return rc; 1715 } 1716 1717 static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required) 1718 { 1719 struct sev_platform_init_args init_args = {0}; 1720 int rc; 1721 1722 rc = _sev_platform_init_locked(&init_args); 1723 if (rc) { 1724 argp->error = SEV_RET_INVALID_PLATFORM_STATE; 1725 return rc; 1726 } 1727 1728 *shutdown_required = true; 1729 1730 return 0; 1731 } 1732 1733 static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required) 1734 { 1735 int error, rc; 1736 1737 rc = __sev_snp_init_locked(&error, 0); 1738 if (rc) { 1739 argp->error = SEV_RET_INVALID_PLATFORM_STATE; 1740 return rc; 1741 } 1742 1743 *shutdown_required = true; 1744 1745 return 0; 1746 } 1747 1748 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable) 1749 { 1750 int state, rc; 1751 1752 if (!writable) 1753 return -EPERM; 1754 1755 /* 1756 * The SEV spec requires that FACTORY_RESET must be issued in 1757 * UNINIT state. Before we go further lets check if any guest is 1758 * active. 1759 * 1760 * If FW is in WORKING state then deny the request otherwise issue 1761 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. 1762 * 1763 */ 1764 rc = sev_get_platform_state(&state, &argp->error); 1765 if (rc) 1766 return rc; 1767 1768 if (state == SEV_STATE_WORKING) 1769 return -EBUSY; 1770 1771 if (state == SEV_STATE_INIT) { 1772 rc = __sev_platform_shutdown_locked(&argp->error); 1773 if (rc) 1774 return rc; 1775 } 1776 1777 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error); 1778 } 1779 1780 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) 1781 { 1782 struct sev_user_data_status data; 1783 int ret; 1784 1785 memset(&data, 0, sizeof(data)); 1786 1787 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error); 1788 if (ret) 1789 return ret; 1790 1791 if (copy_to_user((void __user *)argp->data, &data, sizeof(data))) 1792 ret = -EFAULT; 1793 1794 return ret; 1795 } 1796 1797 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable) 1798 { 1799 struct sev_device *sev = psp_master->sev_data; 1800 bool shutdown_required = false; 1801 int rc; 1802 1803 if (!writable) 1804 return -EPERM; 1805 1806 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) { 1807 rc = sev_move_to_init_state(argp, &shutdown_required); 1808 if (rc) 1809 return rc; 1810 } 1811 1812 rc = __sev_do_cmd_locked(cmd, NULL, &argp->error); 1813 1814 if (shutdown_required) 1815 __sev_firmware_shutdown(sev, false); 1816 1817 return rc; 1818 } 1819 1820 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable) 1821 { 1822 struct sev_device *sev = psp_master->sev_data; 1823 struct sev_user_data_pek_csr input; 1824 bool shutdown_required = false; 1825 struct sev_data_pek_csr data; 1826 void __user *input_address; 1827 void *blob = NULL; 1828 int ret; 1829 1830 if (!writable) 1831 return -EPERM; 1832 1833 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 1834 return -EFAULT; 1835 1836 memset(&data, 0, sizeof(data)); 1837 1838 /* userspace wants to query CSR length */ 1839 if (!input.address || !input.length) 1840 goto cmd; 1841 1842 /* allocate a physically contiguous buffer to store the CSR blob */ 1843 input_address = (void __user *)input.address; 1844 if (input.length > SEV_FW_BLOB_MAX_SIZE) 1845 return -EFAULT; 1846 1847 blob = kzalloc(input.length, GFP_KERNEL); 1848 if (!blob) 1849 return -ENOMEM; 1850 1851 data.address = __psp_pa(blob); 1852 data.len = input.length; 1853 1854 cmd: 1855 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) { 1856 ret = sev_move_to_init_state(argp, &shutdown_required); 1857 if (ret) 1858 goto e_free_blob; 1859 } 1860 1861 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error); 1862 1863 /* If we query the CSR length, FW responded with expected data. */ 1864 input.length = data.len; 1865 1866 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 1867 ret = -EFAULT; 1868 goto e_free_blob; 1869 } 1870 1871 if (blob) { 1872 if (copy_to_user(input_address, blob, input.length)) 1873 ret = -EFAULT; 1874 } 1875 1876 e_free_blob: 1877 if (shutdown_required) 1878 __sev_firmware_shutdown(sev, false); 1879 1880 kfree(blob); 1881 return ret; 1882 } 1883 1884 void *psp_copy_user_blob(u64 uaddr, u32 len) 1885 { 1886 if (!uaddr || !len) 1887 return ERR_PTR(-EINVAL); 1888 1889 /* verify that blob length does not exceed our limit */ 1890 if (len > SEV_FW_BLOB_MAX_SIZE) 1891 return ERR_PTR(-EINVAL); 1892 1893 return memdup_user((void __user *)uaddr, len); 1894 } 1895 EXPORT_SYMBOL_GPL(psp_copy_user_blob); 1896 1897 static int sev_get_api_version(void) 1898 { 1899 struct sev_device *sev = psp_master->sev_data; 1900 struct sev_user_data_status status; 1901 int error = 0, ret; 1902 1903 /* 1904 * Cache SNP platform status and SNP feature information 1905 * if SNP is available. 1906 */ 1907 if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) { 1908 ret = snp_get_platform_data(sev, &error); 1909 if (ret) 1910 return 1; 1911 } 1912 1913 ret = sev_platform_status(&status, &error); 1914 if (ret) { 1915 dev_err(sev->dev, 1916 "SEV: failed to get status. Error: %#x\n", error); 1917 return 1; 1918 } 1919 1920 /* Cache SEV platform status */ 1921 sev->sev_plat_status = status; 1922 1923 sev->api_major = status.api_major; 1924 sev->api_minor = status.api_minor; 1925 sev->build = status.build; 1926 1927 return 0; 1928 } 1929 1930 static int sev_get_firmware(struct device *dev, 1931 const struct firmware **firmware) 1932 { 1933 char fw_name_specific[SEV_FW_NAME_SIZE]; 1934 char fw_name_subset[SEV_FW_NAME_SIZE]; 1935 1936 snprintf(fw_name_specific, sizeof(fw_name_specific), 1937 "amd/amd_sev_fam%.2xh_model%.2xh.sbin", 1938 boot_cpu_data.x86, boot_cpu_data.x86_model); 1939 1940 snprintf(fw_name_subset, sizeof(fw_name_subset), 1941 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", 1942 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); 1943 1944 /* Check for SEV FW for a particular model. 1945 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h 1946 * 1947 * or 1948 * 1949 * Check for SEV FW common to a subset of models. 1950 * Ex. amd_sev_fam17h_model0xh.sbin for 1951 * Family 17h Model 00h -- Family 17h Model 0Fh 1952 * 1953 * or 1954 * 1955 * Fall-back to using generic name: sev.fw 1956 */ 1957 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || 1958 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || 1959 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) 1960 return 0; 1961 1962 return -ENOENT; 1963 } 1964 1965 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ 1966 static int sev_update_firmware(struct device *dev) 1967 { 1968 struct sev_data_download_firmware data; 1969 const struct firmware *firmware; 1970 int ret, error, order; 1971 struct page *p; 1972 void *fw_blob; 1973 1974 if (!sev_version_greater_or_equal(0, 15)) { 1975 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n"); 1976 return -1; 1977 } 1978 1979 if (sev_get_firmware(dev, &firmware) == -ENOENT) { 1980 dev_dbg(dev, "No SEV firmware file present\n"); 1981 return -1; 1982 } 1983 1984 order = get_order(firmware->size); 1985 p = alloc_pages(GFP_KERNEL, order); 1986 if (!p) { 1987 ret = -1; 1988 goto fw_err; 1989 } 1990 1991 /* 1992 * Copy firmware data to a kernel allocated contiguous 1993 * memory region. 1994 */ 1995 fw_blob = page_address(p); 1996 memcpy(fw_blob, firmware->data, firmware->size); 1997 1998 data.address = __psp_pa(fw_blob); 1999 data.len = firmware->size; 2000 2001 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, &data, &error); 2002 2003 /* 2004 * A quirk for fixing the committed TCB version, when upgrading from 2005 * earlier firmware version than 1.50. 2006 */ 2007 if (!ret && !sev_version_greater_or_equal(1, 50)) 2008 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, &data, &error); 2009 2010 if (ret) 2011 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error); 2012 2013 __free_pages(p, order); 2014 2015 fw_err: 2016 release_firmware(firmware); 2017 2018 return ret; 2019 } 2020 2021 static int __sev_snp_shutdown_locked(int *error, bool panic) 2022 { 2023 struct psp_device *psp = psp_master; 2024 struct sev_device *sev; 2025 struct sev_data_snp_shutdown_ex data; 2026 int ret; 2027 2028 if (!psp || !psp->sev_data) 2029 return 0; 2030 2031 sev = psp->sev_data; 2032 2033 if (!sev->snp_initialized) 2034 return 0; 2035 2036 memset(&data, 0, sizeof(data)); 2037 data.len = sizeof(data); 2038 data.iommu_snp_shutdown = 1; 2039 if (sev->snp_feat_info_0.ecx & SNP_X86_SHUTDOWN_SUPPORTED) 2040 data.x86_snp_shutdown = 1; 2041 2042 /* 2043 * If invoked during panic handling, local interrupts are disabled 2044 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called. 2045 * In that case, a wbinvd() is done on remote CPUs via the NMI 2046 * callback, so only a local wbinvd() is needed here. 2047 */ 2048 if (!panic) 2049 wbinvd_on_all_cpus(); 2050 else 2051 wbinvd(); 2052 2053 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error); 2054 /* SHUTDOWN may require DF_FLUSH */ 2055 if (*error == SEV_RET_DFFLUSH_REQUIRED) { 2056 int dfflush_error = SEV_RET_NO_FW_CALL; 2057 2058 ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error); 2059 if (ret) { 2060 dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n", 2061 ret, dfflush_error); 2062 return ret; 2063 } 2064 /* reissue the shutdown command */ 2065 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, 2066 error); 2067 } 2068 if (ret) { 2069 dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n", 2070 ret, *error); 2071 return ret; 2072 } 2073 2074 if (data.x86_snp_shutdown) { 2075 if (!panic) 2076 snp_shutdown(); 2077 snp_hv_fixed_pages_state_update(sev, ALLOCATED); 2078 } else { 2079 /* 2080 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP 2081 * enforcement by the IOMMU and also transitions all pages 2082 * associated with the IOMMU to the Reclaim state. 2083 * Firmware was transitioning the IOMMU pages to Hypervisor state 2084 * before version 1.53. But, accounting for the number of assigned 2085 * 4kB pages in a 2M page was done incorrectly by not transitioning 2086 * to the Reclaim state. This resulted in RMP #PF when later accessing 2087 * the 2M page containing those pages during kexec boot. Hence, the 2088 * firmware now transitions these pages to Reclaim state and hypervisor 2089 * needs to transition these pages to shared state. SNP Firmware 2090 * version 1.53 and above are needed for kexec boot. 2091 */ 2092 ret = amd_iommu_snp_disable(); 2093 if (ret) { 2094 dev_err(sev->dev, "SNP IOMMU shutdown failed\n"); 2095 return ret; 2096 } 2097 } 2098 2099 snp_leak_hv_fixed_pages(); 2100 sev->snp_initialized = false; 2101 dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n"); 2102 2103 /* 2104 * __sev_snp_shutdown_locked() deadlocks when it tries to unregister 2105 * itself during panic as the panic notifier is called with RCU read 2106 * lock held and notifier unregistration does RCU synchronization. 2107 */ 2108 if (!panic) 2109 atomic_notifier_chain_unregister(&panic_notifier_list, 2110 &snp_panic_notifier); 2111 2112 /* Reset TMR size back to default */ 2113 sev_es_tmr_size = SEV_TMR_SIZE; 2114 2115 return ret; 2116 } 2117 2118 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) 2119 { 2120 struct sev_device *sev = psp_master->sev_data; 2121 struct sev_user_data_pek_cert_import input; 2122 struct sev_data_pek_cert_import data; 2123 bool shutdown_required = false; 2124 void *pek_blob, *oca_blob; 2125 int ret; 2126 2127 if (!writable) 2128 return -EPERM; 2129 2130 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2131 return -EFAULT; 2132 2133 /* copy PEK certificate blobs from userspace */ 2134 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len); 2135 if (IS_ERR(pek_blob)) 2136 return PTR_ERR(pek_blob); 2137 2138 data.reserved = 0; 2139 data.pek_cert_address = __psp_pa(pek_blob); 2140 data.pek_cert_len = input.pek_cert_len; 2141 2142 /* copy PEK certificate blobs from userspace */ 2143 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len); 2144 if (IS_ERR(oca_blob)) { 2145 ret = PTR_ERR(oca_blob); 2146 goto e_free_pek; 2147 } 2148 2149 data.oca_cert_address = __psp_pa(oca_blob); 2150 data.oca_cert_len = input.oca_cert_len; 2151 2152 /* If platform is not in INIT state then transition it to INIT */ 2153 if (sev->sev_plat_status.state != SEV_STATE_INIT) { 2154 ret = sev_move_to_init_state(argp, &shutdown_required); 2155 if (ret) 2156 goto e_free_oca; 2157 } 2158 2159 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error); 2160 2161 e_free_oca: 2162 if (shutdown_required) 2163 __sev_firmware_shutdown(sev, false); 2164 2165 kfree(oca_blob); 2166 e_free_pek: 2167 kfree(pek_blob); 2168 return ret; 2169 } 2170 2171 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) 2172 { 2173 struct sev_user_data_get_id2 input; 2174 struct sev_data_get_id data; 2175 void __user *input_address; 2176 void *id_blob = NULL; 2177 int ret; 2178 2179 /* SEV GET_ID is available from SEV API v0.16 and up */ 2180 if (!sev_version_greater_or_equal(0, 16)) 2181 return -ENOTSUPP; 2182 2183 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2184 return -EFAULT; 2185 2186 input_address = (void __user *)input.address; 2187 2188 if (input.address && input.length) { 2189 /* 2190 * The length of the ID shouldn't be assumed by software since 2191 * it may change in the future. The allocation size is limited 2192 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator. 2193 * If the allocation fails, simply return ENOMEM rather than 2194 * warning in the kernel log. 2195 */ 2196 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); 2197 if (!id_blob) 2198 return -ENOMEM; 2199 2200 data.address = __psp_pa(id_blob); 2201 data.len = input.length; 2202 } else { 2203 data.address = 0; 2204 data.len = 0; 2205 } 2206 2207 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error); 2208 2209 /* 2210 * Firmware will return the length of the ID value (either the minimum 2211 * required length or the actual length written), return it to the user. 2212 */ 2213 input.length = data.len; 2214 2215 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 2216 ret = -EFAULT; 2217 goto e_free; 2218 } 2219 2220 if (id_blob) { 2221 if (copy_to_user(input_address, id_blob, data.len)) { 2222 ret = -EFAULT; 2223 goto e_free; 2224 } 2225 } 2226 2227 e_free: 2228 kfree(id_blob); 2229 2230 return ret; 2231 } 2232 2233 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp) 2234 { 2235 struct sev_data_get_id *data; 2236 u64 data_size, user_size; 2237 void *id_blob, *mem; 2238 int ret; 2239 2240 /* SEV GET_ID available from SEV API v0.16 and up */ 2241 if (!sev_version_greater_or_equal(0, 16)) 2242 return -ENOTSUPP; 2243 2244 /* SEV FW expects the buffer it fills with the ID to be 2245 * 8-byte aligned. Memory allocated should be enough to 2246 * hold data structure + alignment padding + memory 2247 * where SEV FW writes the ID. 2248 */ 2249 data_size = ALIGN(sizeof(struct sev_data_get_id), 8); 2250 user_size = sizeof(struct sev_user_data_get_id); 2251 2252 mem = kzalloc(data_size + user_size, GFP_KERNEL); 2253 if (!mem) 2254 return -ENOMEM; 2255 2256 data = mem; 2257 id_blob = mem + data_size; 2258 2259 data->address = __psp_pa(id_blob); 2260 data->len = user_size; 2261 2262 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error); 2263 if (!ret) { 2264 if (copy_to_user((void __user *)argp->data, id_blob, data->len)) 2265 ret = -EFAULT; 2266 } 2267 2268 kfree(mem); 2269 2270 return ret; 2271 } 2272 2273 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable) 2274 { 2275 struct sev_device *sev = psp_master->sev_data; 2276 struct sev_user_data_pdh_cert_export input; 2277 void *pdh_blob = NULL, *cert_blob = NULL; 2278 struct sev_data_pdh_cert_export data; 2279 void __user *input_cert_chain_address; 2280 void __user *input_pdh_cert_address; 2281 bool shutdown_required = false; 2282 int ret; 2283 2284 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2285 return -EFAULT; 2286 2287 memset(&data, 0, sizeof(data)); 2288 2289 input_pdh_cert_address = (void __user *)input.pdh_cert_address; 2290 input_cert_chain_address = (void __user *)input.cert_chain_address; 2291 2292 /* Userspace wants to query the certificate length. */ 2293 if (!input.pdh_cert_address || 2294 !input.pdh_cert_len || 2295 !input.cert_chain_address) 2296 goto cmd; 2297 2298 /* Allocate a physically contiguous buffer to store the PDH blob. */ 2299 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) 2300 return -EFAULT; 2301 2302 /* Allocate a physically contiguous buffer to store the cert chain blob. */ 2303 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) 2304 return -EFAULT; 2305 2306 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL); 2307 if (!pdh_blob) 2308 return -ENOMEM; 2309 2310 data.pdh_cert_address = __psp_pa(pdh_blob); 2311 data.pdh_cert_len = input.pdh_cert_len; 2312 2313 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL); 2314 if (!cert_blob) { 2315 ret = -ENOMEM; 2316 goto e_free_pdh; 2317 } 2318 2319 data.cert_chain_address = __psp_pa(cert_blob); 2320 data.cert_chain_len = input.cert_chain_len; 2321 2322 cmd: 2323 /* If platform is not in INIT state then transition it to INIT. */ 2324 if (sev->sev_plat_status.state != SEV_STATE_INIT) { 2325 if (!writable) { 2326 ret = -EPERM; 2327 goto e_free_cert; 2328 } 2329 ret = sev_move_to_init_state(argp, &shutdown_required); 2330 if (ret) 2331 goto e_free_cert; 2332 } 2333 2334 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error); 2335 2336 /* If we query the length, FW responded with expected data. */ 2337 input.cert_chain_len = data.cert_chain_len; 2338 input.pdh_cert_len = data.pdh_cert_len; 2339 2340 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 2341 ret = -EFAULT; 2342 goto e_free_cert; 2343 } 2344 2345 if (pdh_blob) { 2346 if (copy_to_user(input_pdh_cert_address, 2347 pdh_blob, input.pdh_cert_len)) { 2348 ret = -EFAULT; 2349 goto e_free_cert; 2350 } 2351 } 2352 2353 if (cert_blob) { 2354 if (copy_to_user(input_cert_chain_address, 2355 cert_blob, input.cert_chain_len)) 2356 ret = -EFAULT; 2357 } 2358 2359 e_free_cert: 2360 if (shutdown_required) 2361 __sev_firmware_shutdown(sev, false); 2362 2363 kfree(cert_blob); 2364 e_free_pdh: 2365 kfree(pdh_blob); 2366 return ret; 2367 } 2368 2369 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp) 2370 { 2371 struct sev_device *sev = psp_master->sev_data; 2372 struct sev_data_snp_addr buf; 2373 struct page *status_page; 2374 void *data; 2375 int ret; 2376 2377 if (!argp->data) 2378 return -EINVAL; 2379 2380 status_page = alloc_page(GFP_KERNEL_ACCOUNT); 2381 if (!status_page) 2382 return -ENOMEM; 2383 2384 data = page_address(status_page); 2385 2386 /* 2387 * SNP_PLATFORM_STATUS can be executed in any SNP state. But if executed 2388 * when SNP has been initialized, the status page must be firmware-owned. 2389 */ 2390 if (sev->snp_initialized) { 2391 /* 2392 * Firmware expects the status page to be in Firmware state, 2393 * otherwise it will report an error INVALID_PAGE_STATE. 2394 */ 2395 if (rmp_mark_pages_firmware(__pa(data), 1, true)) { 2396 ret = -EFAULT; 2397 goto cleanup; 2398 } 2399 } 2400 2401 buf.address = __psp_pa(data); 2402 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error); 2403 2404 if (sev->snp_initialized) { 2405 /* 2406 * The status page will be in Reclaim state on success, or left 2407 * in Firmware state on failure. Use snp_reclaim_pages() to 2408 * transition either case back to Hypervisor-owned state. 2409 */ 2410 if (snp_reclaim_pages(__pa(data), 1, true)) 2411 return -EFAULT; 2412 } 2413 2414 if (ret) 2415 goto cleanup; 2416 2417 if (copy_to_user((void __user *)argp->data, data, 2418 sizeof(struct sev_user_data_snp_status))) 2419 ret = -EFAULT; 2420 2421 cleanup: 2422 __free_pages(status_page, 0); 2423 return ret; 2424 } 2425 2426 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp) 2427 { 2428 struct sev_device *sev = psp_master->sev_data; 2429 struct sev_data_snp_commit buf; 2430 bool shutdown_required = false; 2431 int ret, error; 2432 2433 if (!sev->snp_initialized) { 2434 ret = snp_move_to_init_state(argp, &shutdown_required); 2435 if (ret) 2436 return ret; 2437 } 2438 2439 buf.len = sizeof(buf); 2440 2441 ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error); 2442 2443 if (shutdown_required) 2444 __sev_snp_shutdown_locked(&error, false); 2445 2446 return ret; 2447 } 2448 2449 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable) 2450 { 2451 struct sev_device *sev = psp_master->sev_data; 2452 struct sev_user_data_snp_config config; 2453 bool shutdown_required = false; 2454 int ret, error; 2455 2456 if (!argp->data) 2457 return -EINVAL; 2458 2459 if (!writable) 2460 return -EPERM; 2461 2462 if (copy_from_user(&config, (void __user *)argp->data, sizeof(config))) 2463 return -EFAULT; 2464 2465 if (!sev->snp_initialized) { 2466 ret = snp_move_to_init_state(argp, &shutdown_required); 2467 if (ret) 2468 return ret; 2469 } 2470 2471 ret = __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error); 2472 2473 if (shutdown_required) 2474 __sev_snp_shutdown_locked(&error, false); 2475 2476 return ret; 2477 } 2478 2479 static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable) 2480 { 2481 struct sev_device *sev = psp_master->sev_data; 2482 struct sev_user_data_snp_vlek_load input; 2483 bool shutdown_required = false; 2484 int ret, error; 2485 void *blob; 2486 2487 if (!argp->data) 2488 return -EINVAL; 2489 2490 if (!writable) 2491 return -EPERM; 2492 2493 if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input))) 2494 return -EFAULT; 2495 2496 if (input.len != sizeof(input) || input.vlek_wrapped_version != 0) 2497 return -EINVAL; 2498 2499 blob = psp_copy_user_blob(input.vlek_wrapped_address, 2500 sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick)); 2501 if (IS_ERR(blob)) 2502 return PTR_ERR(blob); 2503 2504 input.vlek_wrapped_address = __psp_pa(blob); 2505 2506 if (!sev->snp_initialized) { 2507 ret = snp_move_to_init_state(argp, &shutdown_required); 2508 if (ret) 2509 goto cleanup; 2510 } 2511 2512 ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error); 2513 2514 if (shutdown_required) 2515 __sev_snp_shutdown_locked(&error, false); 2516 2517 cleanup: 2518 kfree(blob); 2519 2520 return ret; 2521 } 2522 2523 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) 2524 { 2525 void __user *argp = (void __user *)arg; 2526 struct sev_issue_cmd input; 2527 int ret = -EFAULT; 2528 bool writable = file->f_mode & FMODE_WRITE; 2529 2530 if (!psp_master || !psp_master->sev_data) 2531 return -ENODEV; 2532 2533 if (ioctl != SEV_ISSUE_CMD) 2534 return -EINVAL; 2535 2536 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) 2537 return -EFAULT; 2538 2539 if (input.cmd > SEV_MAX) 2540 return -EINVAL; 2541 2542 mutex_lock(&sev_cmd_mutex); 2543 2544 switch (input.cmd) { 2545 2546 case SEV_FACTORY_RESET: 2547 ret = sev_ioctl_do_reset(&input, writable); 2548 break; 2549 case SEV_PLATFORM_STATUS: 2550 ret = sev_ioctl_do_platform_status(&input); 2551 break; 2552 case SEV_PEK_GEN: 2553 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable); 2554 break; 2555 case SEV_PDH_GEN: 2556 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable); 2557 break; 2558 case SEV_PEK_CSR: 2559 ret = sev_ioctl_do_pek_csr(&input, writable); 2560 break; 2561 case SEV_PEK_CERT_IMPORT: 2562 ret = sev_ioctl_do_pek_import(&input, writable); 2563 break; 2564 case SEV_PDH_CERT_EXPORT: 2565 ret = sev_ioctl_do_pdh_export(&input, writable); 2566 break; 2567 case SEV_GET_ID: 2568 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n"); 2569 ret = sev_ioctl_do_get_id(&input); 2570 break; 2571 case SEV_GET_ID2: 2572 ret = sev_ioctl_do_get_id2(&input); 2573 break; 2574 case SNP_PLATFORM_STATUS: 2575 ret = sev_ioctl_do_snp_platform_status(&input); 2576 break; 2577 case SNP_COMMIT: 2578 ret = sev_ioctl_do_snp_commit(&input); 2579 break; 2580 case SNP_SET_CONFIG: 2581 ret = sev_ioctl_do_snp_set_config(&input, writable); 2582 break; 2583 case SNP_VLEK_LOAD: 2584 ret = sev_ioctl_do_snp_vlek_load(&input, writable); 2585 break; 2586 default: 2587 ret = -EINVAL; 2588 goto out; 2589 } 2590 2591 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) 2592 ret = -EFAULT; 2593 out: 2594 mutex_unlock(&sev_cmd_mutex); 2595 2596 return ret; 2597 } 2598 2599 static const struct file_operations sev_fops = { 2600 .owner = THIS_MODULE, 2601 .unlocked_ioctl = sev_ioctl, 2602 }; 2603 2604 int sev_platform_status(struct sev_user_data_status *data, int *error) 2605 { 2606 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error); 2607 } 2608 EXPORT_SYMBOL_GPL(sev_platform_status); 2609 2610 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) 2611 { 2612 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error); 2613 } 2614 EXPORT_SYMBOL_GPL(sev_guest_deactivate); 2615 2616 int sev_guest_activate(struct sev_data_activate *data, int *error) 2617 { 2618 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error); 2619 } 2620 EXPORT_SYMBOL_GPL(sev_guest_activate); 2621 2622 int sev_guest_decommission(struct sev_data_decommission *data, int *error) 2623 { 2624 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error); 2625 } 2626 EXPORT_SYMBOL_GPL(sev_guest_decommission); 2627 2628 int sev_guest_df_flush(int *error) 2629 { 2630 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); 2631 } 2632 EXPORT_SYMBOL_GPL(sev_guest_df_flush); 2633 2634 static void sev_exit(struct kref *ref) 2635 { 2636 misc_deregister(&misc_dev->misc); 2637 kfree(misc_dev); 2638 misc_dev = NULL; 2639 } 2640 2641 static int sev_misc_init(struct sev_device *sev) 2642 { 2643 struct device *dev = sev->dev; 2644 int ret; 2645 2646 /* 2647 * SEV feature support can be detected on multiple devices but the SEV 2648 * FW commands must be issued on the master. During probe, we do not 2649 * know the master hence we create /dev/sev on the first device probe. 2650 * sev_do_cmd() finds the right master device to which to issue the 2651 * command to the firmware. 2652 */ 2653 if (!misc_dev) { 2654 struct miscdevice *misc; 2655 2656 misc_dev = kzalloc_obj(*misc_dev); 2657 if (!misc_dev) 2658 return -ENOMEM; 2659 2660 misc = &misc_dev->misc; 2661 misc->minor = MISC_DYNAMIC_MINOR; 2662 misc->name = DEVICE_NAME; 2663 misc->fops = &sev_fops; 2664 2665 ret = misc_register(misc); 2666 if (ret) 2667 return ret; 2668 2669 kref_init(&misc_dev->refcount); 2670 } else { 2671 kref_get(&misc_dev->refcount); 2672 } 2673 2674 init_waitqueue_head(&sev->int_queue); 2675 sev->misc = misc_dev; 2676 dev_dbg(dev, "registered SEV device\n"); 2677 2678 return 0; 2679 } 2680 2681 int sev_dev_init(struct psp_device *psp) 2682 { 2683 struct device *dev = psp->dev; 2684 struct sev_device *sev; 2685 int ret = -ENOMEM; 2686 2687 if (!boot_cpu_has(X86_FEATURE_SEV)) { 2688 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n"); 2689 return 0; 2690 } 2691 2692 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL); 2693 if (!sev) 2694 goto e_err; 2695 2696 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1); 2697 if (!sev->cmd_buf) 2698 goto e_sev; 2699 2700 sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE; 2701 2702 psp->sev_data = sev; 2703 2704 sev->dev = dev; 2705 sev->psp = psp; 2706 2707 sev->io_regs = psp->io_regs; 2708 2709 sev->vdata = (struct sev_vdata *)psp->vdata->sev; 2710 if (!sev->vdata) { 2711 ret = -ENODEV; 2712 dev_err(dev, "sev: missing driver data\n"); 2713 goto e_buf; 2714 } 2715 2716 psp_set_sev_irq_handler(psp, sev_irq_handler, sev); 2717 2718 ret = sev_misc_init(sev); 2719 if (ret) 2720 goto e_irq; 2721 2722 dev_notice(dev, "sev enabled\n"); 2723 2724 return 0; 2725 2726 e_irq: 2727 psp_clear_sev_irq_handler(psp); 2728 e_buf: 2729 devm_free_pages(dev, (unsigned long)sev->cmd_buf); 2730 e_sev: 2731 devm_kfree(dev, sev); 2732 e_err: 2733 psp->sev_data = NULL; 2734 2735 dev_notice(dev, "sev initialization failed\n"); 2736 2737 return ret; 2738 } 2739 2740 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic) 2741 { 2742 int error; 2743 2744 __sev_platform_shutdown_locked(&error); 2745 2746 if (sev_es_tmr) { 2747 /* 2748 * The TMR area was encrypted, flush it from the cache. 2749 * 2750 * If invoked during panic handling, local interrupts are 2751 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus() 2752 * can't be used. In that case, wbinvd() is done on remote CPUs 2753 * via the NMI callback, and done for this CPU later during 2754 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped. 2755 */ 2756 if (!panic) 2757 wbinvd_on_all_cpus(); 2758 2759 __snp_free_firmware_pages(virt_to_page(sev_es_tmr), 2760 get_order(sev_es_tmr_size), 2761 true); 2762 sev_es_tmr = NULL; 2763 } 2764 2765 if (sev_init_ex_buffer) { 2766 __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer), 2767 get_order(NV_LENGTH), 2768 true); 2769 sev_init_ex_buffer = NULL; 2770 } 2771 2772 __sev_snp_shutdown_locked(&error, panic); 2773 } 2774 2775 static void sev_firmware_shutdown(struct sev_device *sev) 2776 { 2777 /* 2778 * Calling without sev_cmd_mutex held as TSM will likely try disconnecting 2779 * IDE and this ends up calling sev_do_cmd() which locks sev_cmd_mutex. 2780 */ 2781 if (sev->tio_status) 2782 sev_tsm_uninit(sev); 2783 2784 mutex_lock(&sev_cmd_mutex); 2785 2786 __sev_firmware_shutdown(sev, false); 2787 2788 kfree(sev->tio_status); 2789 sev->tio_status = NULL; 2790 2791 mutex_unlock(&sev_cmd_mutex); 2792 } 2793 2794 void sev_platform_shutdown(void) 2795 { 2796 if (!psp_master || !psp_master->sev_data) 2797 return; 2798 2799 sev_firmware_shutdown(psp_master->sev_data); 2800 } 2801 EXPORT_SYMBOL_GPL(sev_platform_shutdown); 2802 2803 u64 sev_get_snp_policy_bits(void) 2804 { 2805 struct psp_device *psp = psp_master; 2806 struct sev_device *sev; 2807 u64 policy_bits; 2808 2809 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) 2810 return 0; 2811 2812 if (!psp || !psp->sev_data) 2813 return 0; 2814 2815 sev = psp->sev_data; 2816 2817 policy_bits = SNP_POLICY_MASK_BASE; 2818 2819 if (sev->snp_plat_status.feature_info) { 2820 if (sev->snp_feat_info_0.ecx & SNP_RAPL_DISABLE_SUPPORTED) 2821 policy_bits |= SNP_POLICY_MASK_RAPL_DIS; 2822 2823 if (sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) 2824 policy_bits |= SNP_POLICY_MASK_CIPHERTEXT_HIDING_DRAM; 2825 2826 if (sev->snp_feat_info_0.ecx & SNP_AES_256_XTS_POLICY_SUPPORTED) 2827 policy_bits |= SNP_POLICY_MASK_MEM_AES_256_XTS; 2828 2829 if (sev->snp_feat_info_0.ecx & SNP_CXL_ALLOW_POLICY_SUPPORTED) 2830 policy_bits |= SNP_POLICY_MASK_CXL_ALLOW; 2831 2832 if (sev_version_greater_or_equal(1, 58)) 2833 policy_bits |= SNP_POLICY_MASK_PAGE_SWAP_DISABLE; 2834 } 2835 2836 return policy_bits; 2837 } 2838 EXPORT_SYMBOL_GPL(sev_get_snp_policy_bits); 2839 2840 void sev_dev_destroy(struct psp_device *psp) 2841 { 2842 struct sev_device *sev = psp->sev_data; 2843 2844 if (!sev) 2845 return; 2846 2847 sev_firmware_shutdown(sev); 2848 2849 if (sev->misc) 2850 kref_put(&misc_dev->refcount, sev_exit); 2851 2852 psp_clear_sev_irq_handler(psp); 2853 } 2854 2855 static int snp_shutdown_on_panic(struct notifier_block *nb, 2856 unsigned long reason, void *arg) 2857 { 2858 struct sev_device *sev = psp_master->sev_data; 2859 2860 /* 2861 * If sev_cmd_mutex is already acquired, then it's likely 2862 * another PSP command is in flight and issuing a shutdown 2863 * would fail in unexpected ways. Rather than create even 2864 * more confusion during a panic, just bail out here. 2865 */ 2866 if (mutex_is_locked(&sev_cmd_mutex)) 2867 return NOTIFY_DONE; 2868 2869 __sev_firmware_shutdown(sev, true); 2870 2871 return NOTIFY_DONE; 2872 } 2873 2874 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, 2875 void *data, int *error) 2876 { 2877 if (!filep || filep->f_op != &sev_fops) 2878 return -EBADF; 2879 2880 return sev_do_cmd(cmd, data, error); 2881 } 2882 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user); 2883 2884 void sev_pci_init(void) 2885 { 2886 struct sev_device *sev = psp_master->sev_data; 2887 u8 api_major, api_minor, build; 2888 2889 if (!sev) 2890 return; 2891 2892 psp_timeout = psp_probe_timeout; 2893 2894 if (sev_get_api_version()) 2895 goto err; 2896 2897 api_major = sev->api_major; 2898 api_minor = sev->api_minor; 2899 build = sev->build; 2900 2901 if (sev_update_firmware(sev->dev) == 0) 2902 sev_get_api_version(); 2903 2904 if (api_major != sev->api_major || api_minor != sev->api_minor || 2905 build != sev->build) 2906 dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n", 2907 api_major, api_minor, build, 2908 sev->api_major, sev->api_minor, sev->build); 2909 2910 return; 2911 2912 err: 2913 sev_dev_destroy(psp_master); 2914 2915 psp_master->sev_data = NULL; 2916 } 2917 2918 void sev_pci_exit(void) 2919 { 2920 struct sev_device *sev = psp_master->sev_data; 2921 2922 if (!sev) 2923 return; 2924 2925 sev_firmware_shutdown(sev); 2926 } 2927